1. Field of the Invention:
This invention relates to guide apparatus for power tools having a blade and, more particularly, to guide apparatus for power tools including a carrier shoe to which may be secured one of several different types of power tools for guiding the power tool along a straight line cut.
2. Description of the Prior Art:
There have been various types of guide apparatus for power tools having blades, such as sabre saws and circular saws. Most of the guide apparatus for the saws have included an integral guide channel secured to the base plate of the saw. The channel cooperates with a guide flange secured to either a table or to the work which is to be sawed. Typically, the guide apparatus of the prior art includes an upwardly extending flange which is secured adjacent to the desired cut at a fixed distance therefrom. The saw, with its guide channel inverted so as to receive the upwardly extending flange, is placed on the guide apparatus with the channel and flange matingly engaged for movement only along the channel. The saw is then guided as the channel moves along the flange. In some cases, there is a guide channel on each side of the sole plate or shoe of the saw.
Since the guide channel is integral with the sole plate or shoe, each saw must have its own respective sole plate or shoe for use with the guide apparatus. That is, the guide apparatus is designed and adaptable only to one specific make of saw. The prior art does not include a universal guide apparatus which can be used with virtually any saw. Since the sole plates or shoes of the saws include the guide channels, the manufacturers of the saws themselves must include the guide apparatus with the basic saw since the sole plate or shoe is normally not a replaceable item separate and apart from the saw itself. The sole plate or shoe of a saw is normally secured to the saw housing and motor as an integral part thereof, and is not normally replaceable. Accordingly, it is necessary that each manufacturer of saws include some type of guide apparatus either as an optional configuration of a saw or else as a standard item with the saw. If the saw is not to be used with the guide apparatus, nevertheless the guide channels are a part of the saw in prior art apparatus.
One of the inherent problems associated with the development of a universal carrier and guide channel apparatus to fit a number of different saws has been the multiplicity of designs of saw sole plates or shoes. The width of the sole plate or shoe varies from about 2 1/8 inches to about 2 7/8 inches for the most common sabre saws. However, there are saws that vary in width from 31/4 inches to 4 inches, and up to about 51/2 inches. Moreover, some of the shoes are curved upwardly at the front end, and some are flat without any upward curvature. Some have upwardly extending lips on the side edges of the shoes while others are flat. All in all, it appears that there are almost as many variations in sabre saw sole plates, or shoes, as there are manufacturers of such sabre saws, or even more due to variations between models by the same manufacturer.